: im adding a 2nd a/c and heating zone to my house and placing unit in attic on 3rd floor. i have a gas line to the 2nd floor dryer. can i tap into that line or do i need dedicated gas line to the unit? tks much

What is the actual TOTAL BTU demand on your system?

What size service do you have?

What is the total developed lenth of this piping?

What is the BTU rating of the "natural " gas your using? IT Varries from 900 -1,200 BTU per CU FT

What is your in coming pressure?

How much "Free Air" are you allowing for combustion?

CERTAINLY you can take off as many gas lines as you like once you know your actual demand and available supply.

Just hope your not making a deadly mistake in your calculations. Good luck